1. Field of the Invention
This invention relates to telephone control units, or subscriber station sets, and it relates particularly to such units for radiotelephone systems.
2. Prior Art
Telephone station sets are known in the art in many forms including relatively flat, box-type configurations which are freestanding at the end of a wire to be placed in a convenient location chosen by the subscriber. Such locations are known in the art to include, for example, concealed locations such as the inside of a drawer or a closet.
In mobile radiotelephone systems the control unit for a mobile radio unit contains the station set elements required for interfacing the radiotelephone with a subscriber. Such elements are often located in one spot in a vehicle and coupled by a cable to a control processor and radio mounted in other parts of the vehicle. Locating a control unit for a person in the driver's seat of an automobile is often a problem. The control unit is usually located on the dashboard, on the floor, or on a console between front seat passengers in the vehicle. It has also been proposed to mount the control unit on the ceiling of an automobile. However, space within an automobile is always at a premium and there is a growing need to identify out-of-the-way locations for the control unit to reduce the chances that a passenger will by accident strike the unit. As mobile radiotelephone service becomes more widely used, there is also a growing need for a standarized type of location for the control unit which is relatively free of the vagaries of automobile model variations. In addition to all of the foregoing problems, the design must, of course, keep the control unit in a location which is convenient for use by a person in the driver's seat in order to minimize distraction from normal driving functions.
Various items have, in the past, been mounted on automobile visors. For example, mirrors have been so mounted as well as radio transmitters for the remote control of selected equipment external to the motor vehicle. However, these prior items lack many of the functions needed for subscriber use of mobile radiotelephone service. For example, there is no need to operate selected controls often requiring visual identification, nor is there a need to remove an item from the visor and which is still connected to the visor after removal. Thus, radiotelephone service has continued for many years with control units on the dashboard, on the floor, or on consoles.